PayPal.Payflow 5.0.4

Payflow .NET SDK

A .NET SDK for easy integration with the PayPal Payflow Gateway. Supports .NET 8.0 (LTS), .NET 10.0 (LTS), and .NET Framework 4.8.

Note: v5 contains breaking changes from v4. Review the CHANGELOG before upgrading an existing integration.

Requirements

Quick Start

Step 1 — Configure credentials

Credentials are read at runtime — never hardcoded. You have two options:

Option A — Environment variables (recommended for CI/CD and shared machines):

# Windows (PowerShell)
$env:PAYFLOW_USER     = "your_user"
$env:PAYFLOW_VENDOR   = "your_vendor"
$env:PAYFLOW_PARTNER  = "PayPal"
$env:PAYFLOW_PASSWORD = "your_password"

# Linux / macOS / Git Bash
export PAYFLOW_USER=your_user
export PAYFLOW_VENDOR=your_vendor
export PAYFLOW_PARTNER=PayPal
export PAYFLOW_PASSWORD=your_password

Option B — App.config (simple local use):

Open dotNET/SamplesCS/App.config (or SamplesVB/App.config for VB) and fill in your account details:

<add key="PayflowUser"     value="your_user" />
<add key="PayflowVendor"   value="your_vendor" />
<add key="PayflowPartner"  value="PayPal" />
<add key="PayflowPassword" value="your_password" />

Git is pre-configured (--skip-worktree) to ignore local changes to both App.config files so your credentials are never staged or committed.

Priority: Environment variables take precedence over App.config. If any env var is missing the file is used as a fallback.

Step 2 — Run the sample

The fastest way to verify connectivity is the DOSaleComplete sample. Once credentials are set in App.config, run:

# Windows (PowerShell)
cd dotNET
.\run-sample.ps1

# Linux / macOS / Git Bash
cd dotNET
./run-sample.sh

REM Windows (Command Prompt)
cd dotNET
run-sample.bat

Pass vb / -VB to run the Visual Basic sample instead of the C# one.

Building the SDK

cd dotNET/PFProSDK
dotnet build

This produces Payflow_dotNET.dll under bin/Debug/net8.0/, bin/Debug/net10.0/, and bin/Debug/net48/. Use -c Release for release binaries.

Building a NuGet Package

Package metadata is embedded directly in PFProSDK.csproj — no separate .nuspec or nuget.exe is needed.

cd dotNET/PFProSDK
dotnet pack -c Release

Output: bin/Release/PayPal.Payflow.5.0.3.nupkg — a single multi-targeted package containing net8.0, net10.0, and net48 assemblies.

Building with Visual Studio

Open dotNET/Payflow dotNET SDK.sln in Visual Studio 2022 or later. The SDK-style project loads directly with no migration wizard.

Running the Samples

All sample projects target net8.0, net10.0, and net48.

Before running: fill in your credentials in App.config as described in the Quick Start section above.

To run from Visual Studio:

1. Open the solution in Visual Studio.
2. Set SamplesCS (C#) or SamplesVB (VB.NET) as the startup project.
3. Update <StartupObject> in the project file if you want a different entry point than DOSaleComplete.
4. Press F5 or use dotnet run --project SamplesCS -f net8.0.

API Documentation

The Payflow SDK Docs project generates a full API reference website using Sandcastle Help File Builder (SHFB) v2026.3.29.0 or later.

Requirements: Install SHFB from its GitHub releases page. Opening the docs project in Visual Studio also requires the .NET Framework 4.8 targeting pack — install it via VS Installer → Modify → Individual components → ".NET Framework 4.8 targeting pack". This is a VS IDE requirement only; the SHFB command-line build does not need it.

$env:SHFBROOT = "C:\Program Files (x86)\EWSoftware\Sandcastle Help File Builder\"
cd "dotNET/Payflow SDK Docs"
dotnet msbuild PayflowSDKDocs.shfbproj /p:Configuration=Release

Output is written to Payflow SDK Docs/Help/.

Important: Do not open Help/index.html directly in a browser. The SHFB website output requires a local HTTP server — browsers block its JavaScript when loaded via file://. Use the provided scripts to serve it:

cd "dotNET/Payflow SDK Docs"
.\view-docs.ps1        # Windows PowerShell

./view-docs.sh         # Linux / macOS / Git Bash

view-docs.bat          # Windows Command Prompt

Each script installs dotnet-serve automatically (one time) and opens the browser. See Payflow SDK Docs/README.md for additional viewing options.

See also the Payflow Gateway Developer Guide.

Contributing

See CONTRIBUTING.md. PRs are welcome; open an issue first for major changes.

Older Versions

The last v4 SDK binaries are in the SDK Binaries directory.

License

SDK LICENSE